1. Technical Field
The present invention relates to a test wafer unit and a test system. In particular, the present invention relates to a test wafer unit and a test system for testing a plurality of semiconductor chips formed on a semiconductor wafer.
2. Related Art
A know apparatus for testing semiconductor chips is an apparatus that tests pass/fail of each of a plurality of semiconductor chips formed on a semiconductor wafer, as shown in, for example, Patent Document 1. This apparatus may include a probe card that can be electrically connected to a plurality of semiconductor chips en bloc.    Patent Document 1: Japanese Patent Application Publication No. 2002-222839    Patent Document 2: International Publication WO 2003/062837
Generally, a probe card is formed using a print substrate or the like, as shown in Patent Document 2, for example. By forming a plurality of probe pins on the print substrate, the resulting probe card can be electrically connected to a plurality of semiconductor chips en bloc.
One test for a semiconductor chip involves using BOST circuits. In this case, the BOST circuits can be loaded on the probe card, but when a plurality of semiconductor chips on a semiconductor wafer are tested together, a large number of BOST circuits must be loaded thereon and it becomes difficult to mount the BOST circuits on the print substrate of the probe card.
Another test for a semiconductor chip involves using BIST circuits provided in the semiconductor chip. With this method, however, circuits that are not used for actual operation are formed in the semiconductor chip, and this decreases the area in which actual operation circuits of the semiconductor chip can be formed.
There are a variety of tests that can be performed on the semiconductor chips, including a DC test for judging whether the DC power consumed by a semiconductor chip fulfills certain specifications, a function test for judging whether a semiconductor chip outputs a prescribed output signal in response to an input signal, and an analog test for judging whether characteristics of a signal output by a semiconductor chip fulfill certain specifications. When BOST circuits are provided on the print substrate or BIST circuits are provided in the semiconductor chips, however, it becomes difficult to perform such a variety of tests.